The present invention relates to an air bag apparatus arranged to protect an occupant at a collision of a vehicle, and an instrumental panel for supporting the air bag apparatus.
The air bag apparatus for absorbing the impact at the collision of the vehicle is installed inside the instrument panel of the vehicle compartment.
In the recent year, the social and technical request to reduce the weight of the overall vehicle is increased. That is, from a viewpoint of social requirement, the reduction in the emission gas of the vehicle is recognized as an important problem for the preservation of earth environment. It is considered that it is the most rational solution to improve fuel economy by the weight reduction of the vehicle. Therefore, it is requested to reduce the weight of whole components of the vehicle, and also the air bag apparatus.
From the viewpoint of the technical request, the air bag apparatuses are mounted to various parts of the vehicle because of the spread of a side air bag, a curtain air bag, and so on. Through the weight of one air bag apparatus does not have great effect, the weight of all the air bag apparatuses mounted on the vehicle can not be disregarded because many air bag apparatuses are mounted on the vehicle. Even if the air bag apparatuses for lessening or losing the occupant's injury may increase in number in the future, it is not thought that the number of the air bag apparatus decreases, therefore the needs for the art for the weight reduction are by no means small.
Moreover, from the viewpoint of the technical request, it is important to downsize the air bag apparatus. The progress of IT (Information technology) applies in the vehicle, and there is a request to bring an operation function and a control function together in the instrument panel. However, even in the conventional vehicles, the instrument panel has devices for vehicle control (for example, ECU), an air conditioner, and control devices for the air conditioner, and audio systems. Moreover, the air bag apparatus is disposed in the instrument panel, and it is in a difficult situation on a layout. In order to add IT devices and so on to such instrument panel, there are needs to miniaturize already-existing built-in apparatus more highly because there is a limit also in the size of an instrument panel naturally from the function.
For this reason, the development for attaining a weight saving, without spoiling the function of the air bag apparatus is progressing, and the air bag device aiming at a weight saving is also proposed, for example with patent documents 1, 2 and 3.
A patent document 1 (Japanese Patent Application Publication No. 2001-97162) shows an air bag apparatus including a folded air bag, a case having an upper chamber opened in an upper surface, and a lower chamber connected with a lower portion of the upper chamber, and an inflator received in the lower chamber.
The case is made of a sheet of metal plate by stamping with deep drawing. The folded air bag is received in the upper chamber.
The case includes a pair of flange portions each formed by bending from a periphery of the upper surface of the upper chamber. These flange portions are fixed to an instrument panel by fastening members to fix an upper part of the case. A bottom portion of the lower chamber is a vehicle body by fastening members to fix a lower part of the case. The case is made of a sheet of the metal sheet, and accordingly it is possible to reduce manufacturing cost and weight of the air bag apparatus.
A patent document 2 (Japanese Patent Application Publication No. 1993 (H05)-193432) shows an air bag apparatus including an air bag, a inflator of cylinder type or bomb type, and a case having a reinforcement frame member made of metal, and a cover member made of resin material, and located inside the reinforcement frame member. The cover member has a substantially U-shaped cross section. The air bag is received in the case.
A fitting hole is formed in a first end surface of the reinforcement frame member. One end of the inflator is inserted from the fitting hole to the reinforcement frame member, and engaged with a keyhole formed in a second end surface of the reinforcement frame member. Consequently, the inflator is fixed to the reinforcement frame member. The inflator serves as a reinforcement member for the reinforcement frame member.
In the apparatus described in the patent document 2, part of the case is skeleton structure, and it is possible to downsize the air bag apparatus without spoiling the intensity of the case.
A patent document 3 (Japanese Patent Application Publication No. 2003-165409) shows an air bag apparatus including a cylinder type or bomb type inflator, a pair of brackets, fixing members, and a separation cloth. Each end of the inflator is fixed to one bracket. Each fixing member connects between upper portions of the brackets. Each end of the separation cloth is retained, by claws, to one fixing member.
The separation cloth is suspended, in the form of U-shape, between the fixing members to cover a lower opening portion between the brackets. The folded air bag is received above the inflator.
The air bag apparatus described in the patent document 3 does not use the conventional metal case, and it is possible to achieve the light weight of the air bag apparatus.